From 8f860591ffb29738cf5539b6fbf27f50dcdeb380 Mon Sep 17 00:00:00 2001 From: "Zhang, Yanmin" Date: Wed, 22 Mar 2006 00:08:50 -0800 Subject: [PATCH] Enable mprotect on huge pages 2.6.16-rc3 uses hugetlb on-demand paging, but it doesn_t support hugetlb mprotect. From: David Gibson Remove a test from the mprotect() path which checks that the mprotect()ed range on a hugepage VMA is hugepage aligned (yes, really, the sense of is_aligned_hugepage_range() is the opposite of what you'd guess :-/). In fact, we don't need this test. If the given addresses match the beginning/end of a hugepage VMA they must already be suitably aligned. If they don't, then mprotect_fixup() will attempt to split the VMA. The very first test in split_vma() will check for a badly aligned address on a hugepage VMA and return -EINVAL if necessary. From: "Chen, Kenneth W" On i386 and x86-64, pte flag _PAGE_PSE collides with _PAGE_PROTNONE. The identify of hugetlb pte is lost when changing page protection via mprotect. A page fault occurs later will trigger a bug check in huge_pte_alloc(). The fix is to always make new pte a hugetlb pte and also to clean up legacy code where _PAGE_PRESENT is forced on in the pre-faulting day. Signed-off-by: Zhang Yanmin Cc: David Gibson Cc: "David S. Miller" Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: William Lee Irwin III Signed-off-by: Ken Chen Signed-off-by: Nishanth Aravamudan Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-i386/pgtable.h | 5 ++--- include/asm-ia64/pgtable.h | 2 +- include/asm-x86_64/pgtable.h | 4 ++-- include/linux/hugetlb.h | 4 ++++ 4 files changed, 9 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/asm-i386/pgtable.h b/include/asm-i386/pgtable.h index 088a945bf26..ee056c41a9f 100644 --- a/include/asm-i386/pgtable.h +++ b/include/asm-i386/pgtable.h @@ -219,13 +219,12 @@ extern unsigned long pg0[]; * The following only work if pte_present() is true. * Undefined behaviour if not.. */ -#define __LARGE_PTE (_PAGE_PSE | _PAGE_PRESENT) static inline int pte_user(pte_t pte) { return (pte).pte_low & _PAGE_USER; } static inline int pte_read(pte_t pte) { return (pte).pte_low & _PAGE_USER; } static inline int pte_dirty(pte_t pte) { return (pte).pte_low & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return (pte).pte_low & _PAGE_ACCESSED; } static inline int pte_write(pte_t pte) { return (pte).pte_low & _PAGE_RW; } -static inline int pte_huge(pte_t pte) { return ((pte).pte_low & __LARGE_PTE) == __LARGE_PTE; } +static inline int pte_huge(pte_t pte) { return (pte).pte_low & _PAGE_PSE; } /* * The following only works if pte_present() is not true. @@ -242,7 +241,7 @@ static inline pte_t pte_mkexec(pte_t pte) { (pte).pte_low |= _PAGE_USER; return static inline pte_t pte_mkdirty(pte_t pte) { (pte).pte_low |= _PAGE_DIRTY; return pte; } static inline pte_t pte_mkyoung(pte_t pte) { (pte).pte_low |= _PAGE_ACCESSED; return pte; } static inline pte_t pte_mkwrite(pte_t pte) { (pte).pte_low |= _PAGE_RW; return pte; } -static inline pte_t pte_mkhuge(pte_t pte) { (pte).pte_low |= __LARGE_PTE; return pte; } +static inline pte_t pte_mkhuge(pte_t pte) { (pte).pte_low |= _PAGE_PSE; return pte; } #ifdef CONFIG_X86_PAE # include diff --git a/include/asm-ia64/pgtable.h b/include/asm-ia64/pgtable.h index e2560c58384..5890972a69b 100644 --- a/include/asm-ia64/pgtable.h +++ b/include/asm-ia64/pgtable.h @@ -314,7 +314,7 @@ ia64_phys_addr_valid (unsigned long addr) #define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_A)) #define pte_mkclean(pte) (__pte(pte_val(pte) & ~_PAGE_D)) #define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D)) -#define pte_mkhuge(pte) (__pte(pte_val(pte) | _PAGE_P)) +#define pte_mkhuge(pte) (__pte(pte_val(pte))) /* * Macro to a page protection value as "uncacheable". Note that "protection" is really a diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h index 715fd94cf57..a617d364d08 100644 --- a/include/asm-x86_64/pgtable.h +++ b/include/asm-x86_64/pgtable.h @@ -273,7 +273,7 @@ static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; } static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; } -static inline int pte_huge(pte_t pte) { return (pte_val(pte) & __LARGE_PTE) == __LARGE_PTE; } +static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_PSE; } static inline pte_t pte_rdprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; } static inline pte_t pte_exprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; } @@ -285,7 +285,7 @@ static inline pte_t pte_mkexec(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _ static inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; } static inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; } static inline pte_t pte_mkwrite(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; } -static inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | __LARGE_PTE)); return pte; } +static inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_PSE)); return pte; } struct vm_area_struct; diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 68d82ad6b17..fa83836b63d 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -41,6 +41,8 @@ struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write); int is_aligned_hugepage_range(unsigned long addr, unsigned long len); int pmd_huge(pmd_t pmd); +void hugetlb_change_protection(struct vm_area_struct *vma, + unsigned long address, unsigned long end, pgprot_t newprot); #ifndef ARCH_HAS_HUGEPAGE_ONLY_RANGE #define is_hugepage_only_range(mm, addr, len) 0 @@ -101,6 +103,8 @@ static inline unsigned long hugetlb_total_pages(void) #define free_huge_page(p) ({ (void)(p); BUG(); }) #define hugetlb_fault(mm, vma, addr, write) ({ BUG(); 0; }) +#define hugetlb_change_protection(vma, address, end, newprot) + #ifndef HPAGE_MASK #define HPAGE_MASK PAGE_MASK /* Keep the compiler happy */ #define HPAGE_SIZE PAGE_SIZE -- cgit